This invention relates to cylinders of an internal combustion engine having an adjustable or variable volume.
Conventional cylinders of internal combustion engines have a cylinder chamber of constant size so that there is an unchangeable compression chamber between the top dead center position of the piston and the cylinder head comprising possibly associated valves. As a result, the compression of the fuel-air mixture inside the cylinder chamber cannot be adapted to the respective conditions so as to achieve a high-grade combustion, but is of predetermined invariable order.
Furthermore, DE-AS 11 23 511 discloses an internal combustion engine which comprises a variable compression chamber and whose cylinder head has provided therein a piston which is adjustable by means of a hydraulic actuating device which, in turn, is connected to the gas pedal of the internal combustion engine. The arrangement is here chosen such that when the internal combustion engine is at idle speed, the cylinder head piston is pressed downwards, whereby the compression chamber of the cylinder is reduced, whereas at maximum speed the cylinder head piston is moved into its uppermost position in which the compression chamber is of maximum size. Hence, when the known internal combustion engine is at full speed, i.e., when there is maximum fuel mixture supply, the compression is minimal, resulting in a very incomplete combustion of the fuel mixture so that the fuel consumption of the known internal combustion engine is high.